Real meaning "really" is also nonstandard. So is omitting are from the beginning of the sentence. So is the spelling gonna, although the contraction is frequent in speech.
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snailboatMar 7 '14 at 11:19

3

The whole sentence is very informal. It's hard to care about nice vs nicely when the sentence starts with You gonna slice them up.
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Tim S.Mar 7 '14 at 14:13

As @TimS said, this is an example of informal speech which is not gramatically correct. That being said, in my opinion "...real nicely" would be awkward in this context. I'd choose either "...real nice" or "...really nicely".
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Bob JarvisMar 7 '14 at 14:37

2

If I heard someone say, "You gonna slice them up real nice?", I'd assume he was talking about the members of an opposing street gang, not tomatoes.
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JayMar 7 '14 at 16:24

2 Answers
2

Since the sentence starts with "you gonna," it is impossible to read it as a formal written English sentence. In spoken language in America, "nice" goes here and never "nicely."

However, in formal written language, the context probably calls for an adverb (I am told that even in informal language, adverbs are used here in Britain, but Friends is set in the US.) So I might write "She sliced them very nicely." (Using "real" for "very" is also informal.)

"Are you going to slice them up really nicely?" is of course the grammatically correct sentence, since nicely modifies slice, a verb, and really modifies nicely, itself an adverb. That is what my mother (a retired English professor) would say. On the other hand, most Americans use real instead of really (despite, in my case, my mother's best efforts), especially in conversation. See John Cleese's hilarious sendup of the habit ("Boy, they whooped your hide real good!") in "A Fish Called Wanda" at en.wikiquote.org/wiki/A_Fish_Called_Wanda.
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BobRodesMar 7 '14 at 14:49

Some uneducated Americans use "real" for "very" when speaking informally. This is considered bad grammar when used in writing, and is rarely used by more educated people. At least in my experience.
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JayMar 7 '14 at 16:27

I use "real" for "very" all the time. Your mileage may vary.
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hunterMar 7 '14 at 16:28

I like how the answer by hunter points out that this is a sitcom script. If all the characters spoke in perfectly grammatical sentences, the language might sound stilted, and therefore unrealistic.

I'd also like to point out that nicely might not even be the right word to use; it depends on if the speaker is modifying the verb slice, or the noun tomatoes. In other words, the question could be asking, in essence:

Are you going to slice them up so that the slices come out nice and even?